1. Field of the Invention
This invention relates generally to gravity flow shelving units and, more specifically, to inclined shelves having adjustable track members for ready manipulation of horizontal spacing and location of track members in gravity flow shelves to accommodate product of various shapes and sizes, so as to maximize use of retail shelf space.
2. Description of the Related Art
In order to increase inventory turnover and maximize efficient use of shelf space, retailers increasingly utilize gravity flow shelving systems, wherein inclined shelves are used to stock merchandise. In such shelf systems, consumers are presented with an array of merchandise arranged in parallel tracks on each shelf, generally with only the front-most (or "first-up") unit of merchandise in each individual track being easily accessible. Upon removing this front-most unit of merchandise, the remaining units of like-merchandise in that given track advance, i.e. slide down, toward the front of the shelf, so that the next-successive unit in line becomes the new front-most unit in that track.
Since conventional flat merchandise shelves, e.g., cantilevered or so-called "gondola"-type shelves, allow users to rearrange product on the shelves, such as to find product with later expiration dates, these inclined gravity flow shelving systems help ensure that oldest product is sold first. By making rearrangement of product more difficult, it is found that inventory waste is reduced. The inclined arrangement of the gravity flow shelves also allows greater shelf-space on a given footprint of valuable floor space for the retailer, which is a particular advantage in relatively costly refrigerated aisles and wall units where gravity shelving systems are becoming the industry standard.
In order to further maximize the use of shelf space, various attempts have been made to provide adjustable or indexable shelving, wherein individual track members are horizontally adjustable relative to a shelf frame, so that track members can be placed by a retailer at different customized desired horizontal locations to accommodate merchandise of varying size, i.e. width, and shape on a single inclined shelf.
The general concept of indexable shelf tracks for display shelves started as early as the late 1950's, where Bromberg, U.S. Pat. No. 2,915,193, showed the use of horizontally-spaced, upwardly- and inwardly-open slots along the front and rear of a flat shelf to accommodate vertical wall members at various desired spaced locations along the width of the shelf to form several compartments of desired sizes within the shelf. A shortcoming of such a shelf with variable width spacings, when utilizing upwardly-open slots to receive vertical wall members, is that the wall members can be easily removed by consumers, thereby easily circumventing the purpose of the vertical wall members.
Indexable shelf tracks have also been used in inclined gravity flow racks, such as in U.S. Pat. No. 4,383,614, which shows a plurality of teeth defining inwardly-open notches along the front and rear rails of an inclined shelf to securely receive individual roller track members to facilitate sliding of products on the track members. Each of the roller track members has an inverted generally U-shaped cross-section, with a flat top web having downwardly-projecting straight legs and inwardly-bent runners. The runners slidably receive a plastic clip member to lock the track member in place within a pair of the inwardly-open notches. Such clip members must be separately manufactured, increasing time and cost of production, as well as providing many additional parts for assembly (and possibly inadvertent loss of smaller parts) by the retailer.
In another previous attempt at an indexable gravity flow shelving system, shown in Highsmith, U.S. Pat. No. 4,909,402, longitudinal dividers having resilient legs are received between pegs having upright and transverse portions that define upwardly-open notches. In localized regions, the resilient legs of the longitudinal dividers are biased together by a clip in order to pass the longitudinal divider between desired adjacent pegs, and then the clip is removed to lock the longitudinal dividers in place. Again, a clip member is necessary to assemble the indexable shelf member. In this instance, since the clip is only used at the time of assembly or removal of a longitudinal divider, the clip may again inadvertently become lost, rendering rearrangement of the longitudinal dividers difficult. Furthermore, additional track members to support merchandise are required.
Most all conventional indexable gravity flow shelf systems require the use of track members specially adapted with legs or flanges on the underside thereof to be received in the indexing slots provided along the front and rear rails of the shelf. These legs or flanges are integral parts of the track members, such as shown in German Patent No. 196 09 432, requiring costly machine operations to form the track members having the required shape. As indicated in that German patent, gravity flow shelf tracks can utilize elongated grooved channels along the length of the track members order to reduce friction between merchandise and the upper flat surface of the track. Alternatively, as shown in Spamer, U.S. Pat. No. 5,022,535, elongated, upwardly-extending flow ribs or runners can be provided along the upper flat surface of the track members, which similarly serve to reduce friction between merchandise and the track members. Spamer discloses using adhesive to mount the shelf tracks to the front and rear rails of the inclined shelf, which can undesirably deteriorate over time.
It would be desirable for an indexable gravity flow shelf system to have the ability to utilize the existing flow ribs or slide runners on the upper surface of the track members to lock track members in desired locations along inclined shelves, because such use would eliminate the need for additional legs or flanges on the underside of the track members. However, there is no known prior gravity flow shelving system that uses the friction-reducing flow ribs on the upper surface of the tracks for securely installing the track members.
Another drawback of conventional indexable shelf systems is that the horizontal adjustability of the individual shelf tracks is limited by relatively wide spacing of the slots or apertures heretofore provided on front and rear rails to receive portions of the tracks. A typical center-to-center distance of about 5/16" separates inwardly-open notches between the teeth members along the front and rear rails of finite horizontally-adjustable (i.e., indexable) gravity flow rack systems found in the prior art. However, it would be desirable for an indexable gravity flow shelf system to provide a greater number of shelf track interface points that are spaced more closely together than in such prior art indexable shelf systems, in order to achieve greater finite horizontal adjustability of track members.
It would also be useful to have an indexable gravity flow shelf system that is easy to assemble and for which the individual shelf tracks can be easily rearranged by the retailer, yet still be securely mounted in place once arranged to avoid inadvertent shelf track slippage or dislocation. It would be further desirable if such a shelf track system required no additional clip parts to lock shelf tracks in place or to install (or remove) shelf tracks in (from) desired locations along the width of the shelf. An additional desirable feature would be the ability to retrofit an existing shelf with components that allow the shelf to act as an indexable gravity flow shelf that does not suffer from the drawbacks described above. The manner in which these objectives are accomplished by the present invention is described in the following Brief Summary of the Invention, the Detailed Description of the Invention, and the drawings.